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arXiv · 1509.07565

Moment estimates implied by modified log-Sobolev inequalities

Radosław Adamczak·Witold Bednorz·Paweł Wolff
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Abstract

We study a class of logarithmic Sobolev inequalities with a general form of the energy functional. The class generalizes various examples of modified logarithmic Sobolev inequalities considered previously in the literature. Refining a method of Aida and Stroock for the classical logarithmic Sobolev inequality, we prove that if a measure on $\mathbb{R}^n$ satisfies a modified logarithmic Sobolev inequality then it satisfies a family of $L^p$-Sobolev-type inequalities with non-Euclidean norms of gradients (and dimension-independent constants). The latter are shown to yield various concentration-type estimates for deviations of smooth (not necessarily Lipschitz) functions and measures of enlargements of sets corresponding to non-Euclidean norms. We also prove a two-level concentration result for functions of bounded Hessian and measures satisfying the classical logarithmic Sobolev inequality.

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Radosław Adamczak, Witold Bednorz, Paweł Wolff. 2015-09-24. Moment estimates implied by modified log-Sobolev inequalities. https://arxiv.org/abs/1509.07565

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